Cylinder surfacing tool



June 14, 1955 H. R. BILLETER ET AL 2,710,497

CYLINDER SURFACING TOOL Filed Sept. 50, 195.2 3 SheetsSheet l ggf 6?.

June 14, 1955 H. R. BILLETER E1- AL CYLINDER SURFACING TooL Filed Spt. 30, v1952 5 Sheets-Sheet 2 June 14, 1955 H. R. BILLETER ETAL 2,710,497

CYLINDER SURFACING TOOL Filed Sept. 30, 1952- 3 Sheets-Sheet 3 Patented June 14, 1955 CYLINDER SURFACING TOOL Henry Robert Billeter, Highland Park, and Walter P. Kushmuk, Chicago, Ill., assignors to Ammco Tools, Inc., North Chicago, Ill., a corporation of Illinois Application September 30, 1952, Serial No. 312,344

18 Claims. (Cl. 51184.3)

long as any of the surfacing elements were forced toward the cylinder wall being surfaced, they were all so forced substantially identically. The felts were more subject to wearing away than the stones, and as they wore away and were reduced in dimension, they were continuously biased toward the wall being surfaced and hence they wore out completely before the stones. As a result, many users mistakenly believed the hones were defective, or that the surfacing elements that wore out first were defective. A similar phenomenon occurred even in the case of a hone having only stones, and no felts, where the stones wore u unevenly, although to a lesser degree than in the case of a hone having both stones and felts.

An object, therefore, of ythe present invention is to provide a cylinder surfacing tool having a plurality of surfacing elements, and having a novel construction such as to effectively eliminate uneven wear of the surfacing elcments.

Another object is to provide a rotary cylinder surfacing tool having a plurality of surfacing elements normally biased outwardly and means limiting the expanding movement of the surfacing elements to a relatively minor extent, whereby the tool has suiiicient fiexibility that the surfacing elements follow an uneven cylinder surface but the flexibility is so limited that the tool effectively withstands forces tending to lmove the tool off center with respect to the axis lof the cylinder, and a flexible drive shaft can be'utilized for driving the tool without moving the tool off center to an'objectionable extent.

Another object is to provide a cylinder surfacing tool having novel construction enabling insertion of the tool in a cylinder and removal therefrom with greater facility than has heretofore been possible with previously known devices.

A more specific object is to provide a cylinder surfacing tool having carriers mounted for expansion and contraction and surfacing elements mounted onthe carriers for limited expansion relative thereto, whereby in inserting the tool into a cylinder and removing it therefrom, the surfacing elements can be positioned with respect to the cylinder by adjustment of the carriers which need be adjusted an extent no greater than the limit of movement of the surfacing elements, and the tool can be inserted and removed with greater facility, as for example in eliminating the necessity for manually gripping and collapsing the surfacing elements.

Another object is to provide a cylinder` surfacing tool having a plurality of surfacing elements and means for expanding the elements in unison in response to a setting of the tool, in which a novel construction is provided for expanding the surfacing elements relative to the setting of the tool and means for individually limiting the expanding movement of the surfacing elements in any given setting of the tool, thereby limiting the wear on the surfacing elements indivdually and consequently effectively eliminating uneven wear on the surfacing units.

Still another object is to provide a cylinder surfacing tool having a plurality of surfacing elements mounted on expansible carriers in which means is provided for yieldably expanding the surfacing elements relative to the carriers, whereby the surfacing elements can be individually expanded in any given setting of the carriers.

A further object is to provide a surfacing tool adapted for surfacing cylinders of any of a Wide range of sizes, having a plurality of surfacing elements and means for setting the tool for moving the surfacing elements to a predetermined expanded position, in which novel means is provided for exerting additional, substantially constant yielding expanding pressure on the elements in all set-` tings of the tool.

Another object is to provide a rotary cylinder surfacing tool having a plurality of surfacing elements, in which novel construction is provided for mounting the surfacing elements so that the elements are enabled to yield in radial direction about pivot axes displaced circumferentially from the elements, whereby chattering and vibration are eifectively eliminated.

A more specific object is to provide means for mounting the surfacing elements, as just referred to, in which the elements are normally positively restrained against displacement circurnferentially, while being enabled to yield radially, whereby chattering and vibration are effectively eliminated.

A still further object is to provide a cylinder surfacing tool having a plurality of surfacing elements detachably mounted therein, in which exceedingly simple means is provided enabling mounting of the surfacing elements in the tool and detaching them therefrom easily and quickly.

Another object is to provide a rotary cylinder surfacing tool having a plurality of surfacing elements, in which novel means is provided for detachably mounting the surfacing elements in the tool and in a manner in which engagement of the surfacing elements with the cylinder surface and the forces exerted thereon incident to rotation of the tool retain the surfacing elementsy in place and restrain them against accidental removal.

A further object is to provide a cylinder surfacing' tool having a plurality of surfacing elements, in which the surfacing elements in the tool and in which lthe surfacing elements are stably mounted against accidental displacement in all directions.

Still another object is to provide a cylinder surfacing tool of' the character above referred to that is of exceedingly simple construction.

Another object is to provide a rotary cylinder surfacing i tool of the character above referred to which may be actuated by a flexible rotary driving element connected to the tool, of such construction that the tool is accuratelyy self-centering in the cylinder being surfaced even though the driving element is fiexed to a position at a wide angle with respect to the axis of the tool.

A still further object is to provide a cylinder surfacing tool of the character referred to, in the use of which the following advantages are attained, that are not attainable in the use of previously known tools of this general type, namely, excessive vibration is overcome and consequently longer life of the tool is assured;

`a more accurate finish is formed on the cylinder surface;

and breakage of the abrasive stones used in the tool is eliminated.

Other objects and advantages of the invention will be apparent on reference to the following detail description. taken in conjunction with the accompanying drawings, in which- Fig. l is a side elevational view of the hone of the present invention, with the hone in contracted condition;

Fig. 2 is an enlarged sectional View taken on line 2-2 of Fig. 1;

Fig. 3 is an axial sectional view taken on line 3-3 of Fig. 2;

Fig. 4 is a partial sectional view, oriented according to Fig. 2, including a portion of a cylinder wall, and one of the surfacing elements partially contracted by the cylinder wall;

Fig. 5 is a view similar to Fig. 3 but showing the hone in expanded condition;

Fig. 6 is a fragmentary sectional view taken on line 6-6 of Fig. 2, showing the hone in contracted condition, this view being reversed with respect to Figs. 3 and 5, so as to more clearly show certain details of structure;

Fig. 7 is an exploded perspective view of a surfacing element assembly; and

Fig. 8 is an enlarged view of one of the end members of the hone, taken on line 8-8 of Fig. l.

Referring in detail to the drawings, the improved cylinder surfacing hone of the present invention is shown in its entirety in Fig. l in association with a drive shank. The hone is adapted for grinding or otherwise finishing the inner surface of a cylinder wall, such, for example, as in an engine cylinder. Such surfacing hones are provided with a plurality of abrasive elements, such as stones` and are often provided with both stones and fe1ts, or bufiing guides. The felts are for the purpose of storing up lubricant applied thereto as by dipping the tool in the lubricant. The felts absorb and store up the lubricant and apply it to the cylinder wall for aiding in the abrading action and for preventing dislodged particles of the material of the cylinder wall from flying or scattering to places where not desired. The felts, or buti'ng guides, wear off faster than the stones in those cases where continuous and substantially uniform pressure is applied to the stones and felts in forcing them into engagement with the cylinder wall. ln such circumstances the felts wear out faster than the stones and the user mistakingly believes the tool is defective, or at least that the felts are defective. The hone of the present invention includes a novel construction for limiting the range of r.

movement of the surfacing elements toward the cylinder wall for any given setting of the hone so that if any of the surfacing elements tend to wear faster than others, the wearing action is limited and checked in such a way as to effectively eliminate unequal wearing of the surfacing elements.

The hone 12 includes a body 14 made up of a small number 0f parts namely, a bottom end member 16, a top end member 18, a shaft or stem 2i) and a nut 22. The end members 16 and 18 are referred to as bottom and top end members for convenience in reference thereto, being so designated in relation to the hone being inserted downwardly into a vertically disposed cylinder. rl`he hone includes a plurality of, preferably four, surfacing element assemblies 24. The body above referred to and the four surfacing element assemblies (Fig. 7) together with a pair of contracting garter springs 26 constitute the hone. As the description proceeds it will be seen that the parts making up the hone are relatively small in number, when the numerous advantages of the hone are considered.

The end members 16 and 13 are mounted on the shaft or stem 20 for relative movement axially along the shaft toward and from each other for effecting expansion and contraction of the surfacing element assemblies and thereby adapting the hone to cylinders of different diameters. The top end member 18 is provided with an axial bore 28 for slidably receiving the shaft 20 which is threaded throughout a substantial portion of its length. The bottom end member 16 is provided with a tapped recess 30 for threadedly receiving the end of the shaft 20, the threads being arranged in appropriate direction for rotation of the tool in the direction desired and maintaining the shaft threaded tightly in the recess. The tool is rotated by force applied to the shaft, the shaft having a pin 31for use in connecting the drive shank 32.

The upper or outer surface of the top end member 18 preferably is provided with a central recess 33 for receiving a reduced diameter body portion 34 of the nut 22, the peripheral surface of the nut being knurled for convenience in manually turning the nut on the shaft, in response to which the end members are moved relatively toward each other. In turning of the nut in one direction, the end member 13 is moved axially along the shaft toward the end member 16 and on turning the nut in the other direction, the end member 18 is moved in the opposite direction under the action of the contracting springs 26 in a manner to be referred to later. The end members 16 and 1S which are symmetrical and opposite, are of roughly star-shape as viewed axially. The shape of the end members is best represented in Fig. 8 where the top end member 18 is shown. The inner surface of the end member includes a central portion 36 which may be substantially flat and disposed perpendicular to the axis of rotation as deiined by the axis of the shaft 2). The outer peripheral portions 38 of the inner surfaces of the two end members are inclined radially outwardly and axially away from each other with respect to the two end members, i. e., the counterpart inclined portions of the two end members diverge in radially outward directions. The end members each have a plurality of projections 40 which may be regarded as extending generally radially outwardly. Adjacent each projection 4G is a relatively indented or cut out portion 42 for receiving the ends of the respective surfacing elements and their supporting elements for enabling relatively great contraction, as will be explained more fully later.

The inner surface of each end member is provided with grooves 44 which in the present instance are four in number in correspondence with the number of surfacing elements provided in the hone. The grooves 44 are disposed tangent to a base circle concentric with the axis of rotation, the inner end of each groove terminating adjacent the center of the end member and adjacent to the shaft 20, while the outer end extends outwardly in the projection 4t) and opens outwardly through the end of the projection. The arrangement of the grooves is such as to provide for movement in substantially radial directions of the surfacing elements, the details of which will be brought out later. It will be understood that the corresponding grooves 44 in the two end members i6 and 18 are arranged in axial alignment and accordingly are disposed in opposite and symmetrical position for receiving the surfacing element assemblies. The axially aligned grooves in the two end members diverge radially outwardly and receive correspondingly inclined portions of the surfacing element assemblies whereby a wedging effect is produced between the respective parts for causing expansion of the surfacing elements. Although the grooves 44 are tangent to a base circle concentric with the axis of rotationand are therefore not disposed in radial direction, the term radial expansion is used herein in relation to the effective movement of the surfacing elements. Portions of the surfacing element assemblies move in tangential directions with respect to the base circle mentioned, but the effect of the movement is to produce radial expansion of the surfacing elements.

The surfacing element assemblies 24 are arranged in the body and specifically in the end members 16 and 18 and include carriers arranged for non-yielding expanding and contracting movements. The surfacing elements proper' are mounted on the carriers for yielding radial expanding and contracting movements relative to the carriers. As a result, the hone can be given any setting within a wide range for moving the carriers and thereby the assemblies to the desired predetermined positions and in that setting the surfacing elements are enabled to be yieldingly expanded and contracted within a limited range.

One of such surfacing unit assemblies 24 is illustrated in exploded view in Fig. 7, and includes four main parts, namely, a carrier 46, a leaf spring 48, and a surfacing member including a supporting member or channel 5l) and a surfacing element 52 which, in the present instance, is an abrasive stone. In Fig. 2, there are two abrasive stones 52 illustrated as well as two felts 54, the stones and felts being arranged respectively diametrically opposite each other. The carrier 46 is preferably in the form of a stamping of relatively heavy gauge sheet metal, and includes an inner portion 56 of generally plate-like form and an outer portion 58 substantially perpendicular to the inner portion with an interconnecting portion 60 therebetween. The outer portion 58 has a trailing edge 59 of substantial axial extent for a purpose to be referred to later. The inner portion 56 is provided with side edges 64 diverging upwardly and outwardly, while its inner edge 62 may be straight in axial direction. The diverging or inclined edges 64 are shaped complementally to the grooves 44 and received in the grooves whereby upon relative movement of the end members 16 and 18 toward each other, a wedging effect is produced between the end members and the carriers for expanding the carriers radially outwardly. Each carrier is provided with notches 66 for receiving the contracting springs 26 which may be well known garter springs. In the interconnecting portion 60 is a punched out tongue 68 having an aperture 70 with a substantial dimension in axial direction. The tongue 68 extends substantially perpendicular to the portion 60 so as to be in position for insertion in the aperture l of a tongue of the channel 50. The axially extended edges of the outer portion 58 of the carrier are provided with notches 71 for receiving the ends of the leaf spring 48 which includes a central arcuate body portion 72 and downturned lugs 74 at its ends. The free ends of the lugs 74 are inclined slightly toward each other and upon insertion in the notches 70, frictionally grip the edge surfaces of the notches for retaining the spring therein.

The channel 50 is utilized for mounting the surfacing element or stone 52 thereon and is supported on the carrier 46 for movement with a limited range relative thereto. The channel 50 also is preferably a sheet metal stamping, although it may be of lighter gauge than the carrier 46. The channel includes a top plane-surface portion 76 and a forwardly extending tongue 78, the latter being sheared and punched to form a lug 80 upstanding from the tongue and having its free edge extending rearwardly with respect thereto, the tongue 78 being inclined slightly downwardly from the plane surface portion 76 so as to be substantially perpendicular to the tongue 68 in the assembly (Fig. 2) for aiding in attaching the channel to the carrier. The channel 50 also includes a downwardly or radially inwardly extending flange 82 at the bottom edge of which is a return bend ledge or flange 84 of relatively short dimension in direction perpendicular to the flange 82.

The surfacing element or stone 52 is mounted on the plane surface portion 76 and secured thereto by a suitable cement or other suitable bonding medium. The stone 52 and surface portion 76 are preferably substantially coextensive in length. The felts or bniiing guides 54 are mounted on their respective channels 50 in a similar manner.

The drive shank 32 may be of suitable and well known form and in the present instance includes a tiexible shank proper 90 and a socket element 92 having bayonet slots 94. The socket 92 is fitted over the outer end of the shaft 20 with the ends of the pin 31 received in the bayonet slots in a customary manner. The hone' is adapted for use with either a flexible or a rigid drive shank depending on the circumstances existing. For example, if the cylinder being surfaced is in a position where the drive shank and driving means may be located in axial alignment with the cylinder, a rigid drive shank may be employed, while if the quarters are crowded and the user finds it diicult to position the driving means in the manner mentioned, he may resort to aA place simply by insertion of the lugs 74 in the notches 71 whereupon the springs assume the positions shown in Fig. 3. The channel 50 with the surfacing element 52 mounted thereon is then mounted on the carrier by insertion or" the tongue 78 into the apertures 70 and at the same time depression of the rear portion so that the flange 84 is iitted under the trailing edge 59 of the carrier.

The various elements of the hone assume leading and trailing positions with respect to the direction of rotation of the hone which is indicated by the arrow in Fig. 4. The dimension of the carrier and channel n circumferential direction is such that when the ange 82 engages the trailing edge 59, the lug 80 firmly engages the leading surface of the tongue 63 (Figs. 2 and 4). The

channel 50 with its surfacing unit is therefore relatively" rigidly held against displacement in circumferential directions. The arrangement of the channel 50 and spring 48 is such that the spring normally urges the channel radially outwardly so that the flange 84 engages the inner surface of the portion 58 of the carrier. The flange 84 acts as a fulcrum about which the spring urges the leading portion or tongue 78 radially outwardly and into engagement with the outer edge of the aperture so that the lug 80 is maintained in engagement with the leading surface of the tongue 68. The aperture 70 is,l of

course, of appropriate dimension radially to enable the leading portion or tongue 78 to be depressed against the action of the spring 48 for enabling insertion of the tongue 78 and lug 80 into the aperture, and removalA therefrom, the latter step being accomplished in removing the channel from the carrier.

The spring 48 is set forwardly of the center of the4 surfacing element with respect to the direction of rotation (Fig. 2) so that when the channel and surfacing ele-'y ment are contracted by engagement with the cylinder wall 98 (Fig. 6), the surfacing element acts as a ful` lcrum about which the spring urges the leading portion or tongue 78 radially outwardly for maintaining the lug 80 in engagement with the tongue 68.

For the purpose initially, of expanding the hone and setting the surfacing elements to a position corresponding to the diameter of the cylinder to be surfaced, the nut 22 is turned up on the shaft 20 for moving the end member 18 toward the end member 16, i. e., moving the end members relatively toward each other. The in- ...lclined disposition of the grooves 44 and edges 64 on the 'carriers produces a wedging effect for expanding the carriers generally radially outwardly. The garter springs 26 of course yield under such expanding force and when the nut 22 is turned in the opposite direction, the garter springs 26 operate to contract the surfacing element asy:sernblies radially inwardly. The carriers are expanded in a non-yielding manner by movement of the end members toward each other so that for any given setting of the hone the carriers remain in fixed setting. In the use of the hone for surfacing a cylinder, the

With the carriers 46 thus fitted in the body of the hone, the leaf springs 48 are fitted in position for that carrier assemblies are moved to a position wherein the surfacing elements 52 and 54 define a cylindrical surface of slightly lesser diameter than the cylinder wall whereby the hone can be easily inserted in the cylinder. In such condition of the hone, the channels are in fully expanded position under the influence of the springs 48 with the anges S4 in engagement with the inner surfaces of the carriers. The nut 22 is then turned up until the surfacing elements expand and engage the cylinder wall. The nut is then further turned up to expand the carriers additionally so that the relation between the channels and carriers is similar to that shown in Fig. 4, namely, the surfacing units are contracted relative to the carriers with the flanges 84 spaced radially inwardly from the carriers. The surfacing operation is then commenced by rotating the tool counterclockwise (Figs. 2 and 4). As the surfacing elements 52. and 54 wear down, they expand radially outwardly relative to the carriers under the inuence of the springs 48 and if the surfacing operation is continued for a sufficient length of time for the surfacing elements to wear down an appreciable extent, the flanges S4 engage carriers and limit further expanding movement of the channels and surfacing elements. Thus, when the felts 54 wear down faster than the stones 52, as is usually the case, they will wear only to that depth as determined by the limit of radial expansion of the channels relative to the carriers as above explained. When the outward expansion of the felts is thus limited and further expansion thereof is checked, all of the thrust between the hone and the cylinder wall is imposed on the stones 52 and when these stones wear down to an extent similar to that of the felts, the thrust is again evenly divided between the stones and felts. The hone of the present invention thus eliminates uneven wear of any substantial magnitude, between the surfacing elements.

It also occurs in certain instances that abrasive stones wear unevenly relative to one another. Abrasive stones are not in all cases of uniform density or hardness and when such non-uniformity exists, unevenness in wear tends to occur, although the variation in wear is normally not as great as between stones and felts. However, the hone of the present invention effectively eliminates such uneven wear between stones.

The construction is especially effective for preventing chattering of the hone in a surfacing operation. Each channel 5t) is arranged to function as a lever. Upon contraction of the trailing portion of the channel relative to the carrier, the channel pivots about the point of contact between the lug SQand tongue 68 as a fulcrum. This fulcrum is disposed forwardly of the surfacing element with respect to the direction of rotation of the tool, with the result that the surfacing element drags over the surface of the cylinder wall, and chattering is eliminated. Because of the elimination of chattering. a more accurate surface is produced on the cylinder wall, and the tendency to break the stones and impair other parts of the hone is minimized, with consequent longer life of the hone.

The novel construction of the mounting for the surfacing elements assures that the channels 50 are maintained in accurate position axially of the hone. Such accurate positioning is, of course, necessary to produce a true cylindrical surface. Since the edge surface 59 and the flange 82 are both of substantial axial dimension and since the ange 82 is maintained in firm engagement with the edge 59, the channels are prevented from cocking or angular displacement in the plane of the surface portion 76. It will be recalled also that the dimensions of the channel and carrier are such that circumferential displacement of the channel is prevented. This feature aids in the action of the ange 82 and edge 59 in restraining the channel against angular displacement referred to, namely, in the plane of the surface portion 76. Thus the surfacing elements are maintained in accurate parallelism with the axis of the hone.

All danger of the channels becoming accidentally detached from the carriers during the operation of the hone is eliminated. When the channels and surfacing elements are in contracted position relative to the carriers (Fig. 4), the springs 48, since they are disposed effectively between the surfacing elements and the tongue 68, retain the leading portions or tongues 78 in radially outward position so that the lugs 80 remain in engagement with the tongues 68. A similar effect is produced when the channels are in fully expanded position since in the latter condition, the anges S4 engage the carriers and the springs are thus between the flanges 84 and tongues 68 so that the same effect is produced, namely, the lugs 80 are maintained in engagement with the tongues 68. Thus in all settings of the hone, the channels are prevented from becoming accidentally detached or dislodged from the carriers. Rotation of the tool in the cylinder produces a rocking effect of the channels about the springs, whereby the act of rotating the hone in a surfacing operation tends to maintain the channels locked in position on the carriers.

Another important advantage of the construction of the hone of the invention is that the various parts may be attached and detached in an easy and simple manner. The channel can be detached from the carrier simply by depressing the tongue 78 and drawing the channel rearwardly from the carrier. The carriers can be easily tted in the end members and can readily be detached therefrom after removal of the garter springs 26. The leaf springs 48 can be attached to the carriers simply by pressing them in position by the hand.

A further important advantage is the simplicity of the hone, and of all of its individual parts, in consideration of the advantages attainable in the use thereof.

The grooves 44 are in staggered overlapping relation so that the carriers can bypass the shaft 20 in the contracting movements of the former, being thus not limited by the shaft in contracting movements. The inner edges 62 of the carriers are enabled to extend into positions in close proximity to the next adjacent carriers (Fig. 2). ln the latter position, the ends of the channels and surfacing units overlie the end members 16 and 18 (Figs. l and 3) and are disposed adjacent the projections 40 (Fig. 2). The projections 40 carry the grooves 44 outwardly to a great extent relative to the size of the hone. A wide range of expansion and contraction is accordingly provided for.

The hone is entirely self-centering. When the hone is expanded sufciently that all of the surfacing units engage the cylinder wall, the surfacing units all cooperate to center the hone in the cylinder. If, for example, the felts are worn down so that they are positioned at their -outer limits of expansion and do not effectively operate on the cylinder wall, they nevertheless aid in centering the hone because if the hone should be displaced in one direction or other, in the direction of the felts, the one felt engaging the cylinder wall will be contracted relative to its carrier and the reaction thereto will urge the hone toward center position. The self-centering feature enables the use of a exible drive shank, and even when the drive shank is flexed or bent at a wide angle with respect to the axis of rotation, the hone nevertheless remains in centered position in the cylinder.

lnsertion of the hone in a cylinder and removal therefrom is greatly facilitated. In insertion of the hone, the carriers are simply adjusted for positioning the surfacing elements at a position slightly less than the diameter of the cylinder, and the hone is then inserted after which the carriers are expanded to expand the surfacing elements into engagement with the cylinder wall. In removal of the hone from the cylinder, the carriers are contracted, which carry the surfacing elements in contractiing direction. The carriers need be adjusted an extent no greater than the limit of movement of the surfacing elements relative to the carriers, and because the later exent is quite limited, the adjustment of the carriers required is not great, and in consequence the tool can be inserted and removed quickly and easily. Fur-y thermore, the user need not manually grip the surfacing elements as was required in the case where the surfacing elements were yieldingly moved throughout the full range of expansion of the tool as in previous devices.

Another important and primary advantage of the hone of the present invention is that substantially uniform presf sure is exerted on the surfacing elements independently of the setting of the hone made according to the size of the cylinder to be surfaced. Regardless of the setting of the t hone made according to the setting of the nut 22, the range of yielding expansion of the surfacing elements relative to their carriers is the same in all cases; whether the hone is adjusted for a small cylinder or for a large cylinder, the outward yielding pressure exerted by the leaf springs 48 is the same in all cases and the hone is not subject to wide variation in expanding pressure as between the innermost limit of contraction and outermost limit of expansion as in the case of previously'known devices in which the yielding expanding means operates to expand the surfacing elements throughout the range between the limits mentioned.

In the hone of the present invention, the surfacing elements are expanded by means of the spring 48 independently and without any influence orreaction on any of the other surfacing elements. r

A feature in the simplicity of the hone is that the torque applied to the hone is transmitted from the end member 16 to the end member 18 through the medium of the carriers themselves, thus eliminating ancillary elements of o structure such as bars, keys, etc.

Another advantage of the invention is that since the` channels 50 are all identical regardless of whether stones,

for rotation about the longitudinal axis thereof, a plurality of carriers mounted in the body for radial expansion, a

surfacing element mounted-on each carrier for pivotal' movement about an axis parallel to said axisofrotation and about an axis in a plane transverse thereto, means on said body for expanding the carriers, and means between said carrier and said surfacing element for expanding the` surfacing elements radially outwardly relatively to-the carriers. f-

2. A cylinder surfacing tool comprising abody adapted for rotation about an axis thereof, a plurality of carriers mounted in the body for radial expansion, a surfacing ele-v ment mounted on each carrier for pivotal movement about an axis parallel to said axis of rotation and about an axis,

in a plane transverse thereto, means on said body for nonyieldingly expanding the carriers and means between said carrier and said surfacing element for yieldingly expanding the surfacing elements radially outwardly relatively to the carriers.

3. A cylinder surfacing tool comprising a body including a pair of end members movable relatively to each other inan axial direction, said end members having similarly arranged sets of grooves in their interfacing surfaces disposed in axial arrangement and mutually divergng:

outwardly, carriers having inclined edges fitted in said grooves, the carriers being wedged radially outwardly in` response to axial movement of the endV members toward each other, means on said body for moving the end members toward each other, means yieldingly urging the carriers radially inwardly, a supporting member mounted on.' each carrier for pivotal movement about an axis parallelv to the axis of said body, a surfacing element carriedon said member for movement in a direction generally radially outwardly relatively to the carriers, and means between said carrier and said surfacing member yieldingly urging the surfacing element radially outwardly.

4. A rotatable cylinder hone comprising a body adapted for rotation about the axis thereof and including a pair of end members movable relatively toward and from each other, a plurality of carriers mounted in and between said end members and each including a first portion engageable with the end members and a second portion extending generally circumferentially of the body, a surfacing element detachably mounted on each carrier for pivotal movement thereon about an axis parallel to the axis of rotation of said hone and positioned on the radial outer side of the respective second portion, said end members and carriers having cooperating inclined surfaces in Wedgng engagement whereby the carriers are moved generally radially outwardly in response to axial movement of the end members relatively toward each other, and means on said body for moving the end members toward each other, said end members having means for guiding said carriers in directions for moving the surfacing elements in generally radial directions.

5. A rotatable cylinder hone comprising a body adapted for rotation about the axis thereof and including a pair of axially spaced end members movable relatively toward and from each other, said end members having similarly arranged grooves in their interfacing surfaces disposed in axial alignment, the said grooves in each end member being tangent to a base circle concentric with the axis of rotation, a plurality of carriers mounted in and between said end members and each including a rst portion fitted in said aligned grooves and a second portion disposed at an angle to the rst portion and extending generally circumferentially therefrom in a direction to intersect a radius of the hone parallel to said first portion, a surfacing element mounted on the second portion of each carrier for pivotal movement thereon about an axis parallel to said axis of rotation, said first portions of the carriers and the end members having wedging engagement effective for moving the carriers outwardly in response to movement of the end members toward each other, and means on said body for moving the end members .toward each other.

6. A rotatable hone comprising a body adapted for rotation about the axis thereof, a plurality of carriers mounted in the body for radial expanding and contracting movements, means on said body for expanding the carriers, each carrier including a generally circumferen- .tially .extending portion, a channel mounted on each carrier.. and a surfacing element mounted on the outer faceof .each channel, each channel being mounted for limited .swinging movement on its carrier about an effec# tive 4pivot axisparallel with the axis of rotation and ofiset .from a radius of said body through said surfacing element', and means yieldingly urging the portion of the channel located radially inwardly of said surfacing element and thereby the surfacing element in a generally radially outward direction relative to the carrier and about the pivot axis.

7. A rotatable hone comprising a body, a plurality of carriers mounted in the body for generally radial expanding and contracting movements, means on said body for expanding the carriers, each carrier including a generally circumferentially extending portion, a channel mounted on each carrier and having a leading portion detachably extending through an aperture in the carrier, with a radially outwardly extending lug engageable with a marginal edge portion of the aperture, each channel having a surfacing element mounted on its trailing portion, and spring means interposed between the carrier and channel and positioned effectively between the surfacing element and said lug andkoperative for yieldingly urging the trailing portion of the channel radially outwardly relative to the carrier.

8. A rotatable hone comprising a body, a plurality of carriers mounted in the body for generally radial expanding and contracting movements, means on said body for expanding the carriers, each carrier including a generally circumferentially extending portion, a channel mounted on each carrier and having a leading portion detachably extending through an aperture in the carrier with a radially outwardly extending lug engageable with the marginal edge portion of the aperture, each channel having a surfacing element mounted on its trailing portion, and spring means interposed between the carrier and channel positioned effectively between the surfacing element and said lug and operative for yieldingly urging the trailing portion of the channel radially outwardly relative to the carrier, the trailing portion of the channel having stop means engageable with the carrier for limiting the radial outward movement of the trailing portion of the channel, said spring means when said stop means is in engagement with the carrier acting on the channel about said stop means as a fulcrum for retaining the leading end of the latter in radially outward position, and when the hone is in a cylinder and the trailing end of the channel is positioned inwardly of its outermost position acting on the channel through the surfacing element and cylinder surface as a fulcrum for retaining the leading end of the channel in radially outward position.

9. A rotary cylinder hone comprising a body including a pair of complementary, relatively axially movable end members of generally star-shape, said end members having generally radially extending projections and having axially aligned grooves in their interfacing surfaces extending outwardly through said projections, a plurality of carriers having first portions fitted in respectively aligned grooves and second portions extending generally circumferentially from the first portions, surfacing units mounted on said second portions of substantial axial length and adapted to overlie said end members adjacent to the projections thereon, said carriers throughv their said first portions and end members having wedging engagement effective for expanding the carriers in generally radial direction in response to movement of the end members toward each other, and means on said body for moving the end members toward each other.

10. A rotary cylinder hone comprising a body including a pair of relatively axially movable end members, means on said body for moving the end members relatively toward each other, and a plurality of surfacing element assemblies mounted in the body for generally radial expanding movement in response to relative movement of the end members in one direction, each assembly including a carrier having an outer, generally circumferentially extendig portion with a trailing edge of substantial axial extent, a channel mounted on the carrier with a trailing edge surface of substantial axial extent in engagement with the trailing edge of the carrier and a leading portion detachably secured in the carrier in securement precluding circumferential movement of the channel relative to the carrier, at least the trailing portion of the channel being movable generally radially relatively to the carrier, means yieldingly urging the channel radially outwardly, the trailing portion of the channel having stop means engageable with the carrier for limiting the outward movement of the channel relative to the carrier, and a surfacing element mounted on the channel rearwardly of the leading end thereof.

ll. A rotary cylinder hone comprising a body including a pair of relatively axially movable end members, means on said body for moving the end members relatively toward each other, and a plurality of surfacing element assemblies mounted in the body for generally radial expanding movement in response to relative movement of the end members in one direction, each assembly including a carrier having an inner portion tangent to a base circle concentric with the axis of rotation and an outer prtion disposed at an angle to the inner portion and extending` generally circumferentially and rearwardly therefrom, said carrier having an outwardly extending tongue adjacent the juncture of the two portions with an axially extending aperture, and an outer portion having a trailing edge of substantial axial extent, a channel detachably mounted on the carrier having a substantial radial surface adjacent its trailing edge of substantial axial extent in engagement with the trailing edge of the carrier and a ange engageable with the inner side of the outer portion of the carrier, said channel also having a forwardly extending tongue with a radially outwardly extending lug removably extending into said aperture with the lug engageable with the tongue on the carrier, the inter-engageable portions of the channel and carrier being so dimensioned as to normally substantially preclude circumferential displacement of the channel relative to the carrier, and yieldable spring means interposed between the carrier and channel operative for urging the channel radially outwardly.

12. A rotary cylinder hone comprising a shaft, a pair of end members mounted on the shaft for relative movement thereon toward and from each other, means on said body for relatively moving the end members toward each other, said end members having axially aligned grooves in their interfacing surfaces tangent to a base circle concentric with the axis of rotation extending from adjacent the shaft outwardly, the respective axially aligned grooves diverging in outward directions, a plurality of carriers each having an inner portion fitted in one of said aligned grooves with inclined side edges complementary to the inclination of the grooves and an outer portion extending generally circumferentially from the inner portion in a direction to intersect a radius of said hone parallel to said inner portion, said outer portion having a free edge of substantial axial extent and notches in its axially outer edges, and the carrier also having an outwardly extending tongue adjacent the juncture of the two said portions with an axially extending aperture, a channel detachably mounted on the carrier having a substantial radial surface of substantial axial extent adjacent an edge thereof and in engagement with the free edge of the carrier, and a flange engageable with the inner side of the outer portion of the carrier, said channel also having a tongue with a radially outwardly extending lug removably extending into said aperture with the lug engageable with the tongue -on the carrier, the inter-engageable portions of the channel and carrier being so dimensioned as to normally substantially preclude circumferential displacement of the channel relative to the carrier, a leaf spring detachably interposed between said carrier and channel for yieldingly urging the channel outwardly and having lugs detachably fitted in said notches and frictionally engaging the carrier, and garter springs surrounding the carriers for yieldingly urging the carriers in contracting direction.

13. A rotatable cylinder hone comprising a body adapted for rotation about the axis thereof, a plurality of carriers mounted on said body for expansion and contraction movement thereon, means engageable with said carriers for contracting them, means on said body for expanding saidcarriers, each of said carriers having an inner portion movable along a plane tangent to a base circle concentric with the axis of rotation of said hone and an outer portion extending generally circumferentially from said first portion in a direction to intersect a radial plane parallel to said first portion, a supporting member connected to said carrier for pivotal movement thereon about a pivot axis generally parallel to said axis of rotation, and having a portion outwardly of the outer portion of said carrier and extending generally circumferentially from said pivot axis, a surfacing element carried on said supporting member outwardly thereof, and resilient means between said carrier and said supporting member for urging the latter and thereby said surfacing element outwardly about said pivot aXlS.

14. A surfacing unit for a rotatable cylinder hone comprising a carrier having a body portion and a ange portion extending from a side edge of said body portion and in a plane at an angle to the plane of said body pornon, a supporting member connected to said carrier for pivotal movement thereon about an axis generally parallel to the plane of said body portion and about an axis in a plane transverse thereto, a surfacing element carried on the side of said supporting member away from the flange portion of said carrier, and resilient means between said flange portion and said supporting member for urging the latter about said rst pivot axis outwardly away from said flange portion.

15. A surfacing unit for a rotatable cylinder hone comprising a carrier having a body portion and a ilange portion extending from a side edge of said body portion and in a plane at an angle to the plane of said body portion, a supporting member connected to said carrier for pivotal movement thereon about an axis generally parallel to the plane of said body portion and about an axis in a plane transverse thereto, a surfacing element carried on said supporting member on the side away from the flange portion of said carrier, resilient means between said flange portion and said supporting member for urging the latter about said first pivot axis outwardly away from said ange portion and means on said supporting member engageable with said flange portion for limiting the outward movement of said supporting member.

16. A surfacing unit for a rotatable cylinder hone comprising a carrier having a body portion, a ange portion extending from a side edge of said body portion and in a plane at an angle to the plane of said body portion and an apertured tongue adjacent the juncture of said body and said flange, a supporting member having a tongue extending through said aperture and detachably engaging said first tongue for connecting said supporting member to said carrier for pivotal movement thereon about an axis generally parallel to the plane of said body portion and about an axis in a plane transverse thereto, a surfacing element carried on the side of said supporting member away from the flange portion of said carrier, and resilient means between said llange portion and said supporting member for urging the latter about said rst pivot axis outwardly away from said ange portion.

17. A surfacing unit for a rotatable cylinder hone comprising a carrier having a body portion, a flange portion extending from a side edge of said body portion and in a plane at an angle to the plane of said body portion, a supporting member connected to said carrier for pivotal movement thereon about an axis generally parallel to the plane of said body portion and about an axis in a plane transverse thereto, a surfacing element carried' on the side of said supporting member away from the flange portion of said carrier and a bowed leaf spring having its ends engaging the end edges of said flange portion and its intermediate portion abutting said supporting member for urging the latter about said first pivot axis outwardly away from said ilange portion.

18. A surfacing member for a cylinder surfacing hone comprising a supporting member having an elongate body, a flange extending substantially perpendicularly from a longitudinal edge thereof in a direction away from a irst face of said body, said flange having an outer free edge portion of less width than said body turned inwardly and substantially parallel to the other face of said body, and a tongue extending from the other longitudinal edge of said body centrally thereof and in a direction away from said ange, and an abrasive stone adhesively carried on the first face of said body.

References Cited in the ile of this patent UNTED STATES PATENTS 250,736 lngalsbe Dec. 13, 1881 267,132 Belding Nov. 7, 1882 784,547 Card Mar. 14, 1905 1,397,660 Reuze Nov. 22, 1921 1,418,847 Stimson lune 6, 1922 1,591,967 Emerson July 13, 1926 1,738,443 Meaux Dec. 3, 1929 1,739,956 Emerson Dec. 17, 1929 2,020,589 Sunnen Nov. 12, 1935 2,040,281 Sunnen May 12, 1936 2,449,012 Schley Sept. 7, 1948 2,560,727 Keiser July 17, 1951 

